The invention relates to a receiving device as defined in the opening part of claim 1, to a recording device as defined in the opening part of claim 8, and to a television set as defined in the opening part of claim 9.
Such a receiving device as defined in the opening part of claim 1 is known from the document xe2x80x9cResearch Disclosure 36853, December 1994xe2x80x9d and takes the form of a teletext decoder. The known teletext decoder has character set storage means in which character codes and associated character information of a character set for countries of the Central European region are stored. In order to deal with national differences of the character sets of European countries the character set storage means store eight character sub-sets of the character set for Central Europe, which each comprise a given number of country-specific characters. There are, for example, country-specific character sub-sets for the language French or Swedish, which each define a number of 13 character data within the character set.
Teletext information and VPS information, which include character codes and additional information can be transmitted in hidden lines of a television signal, so-called VBI lines (Vertical Blanking Information). The teletext specification (ETS 300 706) specifies that a header row of each teletext page contains three control bits (National Option Character Sub-Set Bit: C12, C13, C14) which form character sub-set information and which specify the appropriate character sub-set of the character set for character codes of this teletext page.
The known teletext decoder includes VBI read-out means which read out the teletext information of a teletext side selected by a user and store this information in page storage means. Detection means of the teletext decoder inter alia detect also the three control bits of the header row of the stored teletext information in order to define the appropriate character sub-set for the decoding of the character codes of the teletext information.
Subsequently, display signal generating means of the teletext decoder are adapted to decode the character codes contained in the stored teletext information. The display signal generating means derive reproducible character information from the appropriate character sub-set for each character code contained in the stored teletext information and supply said character information as a display signal. The display signal can be applied to a monitor and the character information can be displayed as teletext information text by means of the monitor.
It has proved to be a disadvantage of the known teletext decoder that the character set storage means of the teletext decoder store only one character set which cannot be used for the decoding of character codes of television signals of other regions, such as for example the Arab countries, Russia or Greece.
It is an object of the invention to provide a receiving device by means of which character codes received in teletext information and relating to at least two regions can be decoded. This object is achieved in a receiving device by the measures defined in the characterizing part of claim 1.
Thus, it is achieved that at least two character sets for two different regions are stored in the character set storage means. In order to select the appropriate character set for the decoding of character codes contained in teletext information, the detection means are adapted to detect program source information or country information. The TV station which transmits the television signal containing the received teletext information is identified by program source information transmitted as additional information in VBI lines. Country information transmitted as additional information in VBI lines identifies the country where the television signal containing the received teletext information is transmitted.
This yields the advantage that receiving devices in accordance with the invention can be incorporated in, for example, television sets, video recorders or combination apparatuses, which can be sold and used in a plurality of different regions. Advantageously, such apparatuses are adapted to display teletext information with the appropriate character set, which information may be contained in television signals which can be received, for example via satellite, in a plurality of different regions.
The measures defined in claim 2 yield the advantage that in the table storage stage each item of program source information or country information is stored in correlation with character set information which designates an appropriate character set stored in the character set storage means.
The measures defined in claim 3 and claim 4 yield the advantage that an appropriate character set can be selected even in the absence of program source information and country information in additional information read out of VBI lines.
The measures defined in claim 5 yield the advantage that program source information and country information laid down in the VPS standard and the teletext standard can be read and detected and that no new additional information must be transmitted in VBI lines.
In accordance with the measures defined in claim 6 a character set, a twisted character set and up to eight character sub-sets can be stored for each region. The teletext specification defines a change-over between the appropriate character set and the appropriate twisted character set of a region by means of additional information included in the teletext information. This yields the advantage that the character set storage means can also store twisted character sets for a plurality of regions.
The measures defined in claims 8 and 9 provide a video recorder and a television set including a recording device, which have the afore-mentioned advantages of a receiving device in accordance with the invention.